ACTIONSCRIPT 3 Developer’s Guide en

Chapter 42: Basics of networking and
communication
Flash Player 9 and later, Adobe AIR 1.0 and later
When you build applications in Flash Player or AIR, you often need to access resources outside your application. For
example, you might send a request for an image to an Internet web server and get the image data in return. Or, you
might send serialized objects back and forth over a socket connection with an application server. The Flash Player and
AIR APIs provide several classes that allow your applications to participate in this exchange. These APIs support IPbased
networking for protocols like UDP, TCP, HTTP, RTMP, and RTMFP.
The following classes can be used to send and receive data across a network:
Class Supported data formats Protocols Description
Loader SWF, PNG, JPEG, GIF HTTP, HTTPS Loads supported data types and converts the
data into a display object.
URLLoader Any (text, XML, binary,
etc.)
See “Loading display content dynamically” on
page 198.
HTTP, HTTPS Loads arbitrary formats of data. Your
application is responsible for interpreting the
data.
FileReference Any HTTP
See “Using the URLLoader class” on page 814
Upload and download files.
NetConnection Video, audio, ActionScript
Message Format (AMF)
HTTP, HTTPS,
RTMP, RTMFP
Often, when creating a web application it is helpful to store persistent information about the user’s application state.
HTML pages and applications typically use cookies for this purpose. In Flash Player, you can use the SharedObject
class for the same purpose. See “Shared objects” on page 700. (The SharedObject class can be used in AIR applications,
but there are fewer restrictions when just saving the data to a regular file.)
Last updated 6/6/2012
See “Using the FileReference class” on
page 652
Connects to video, audio and remote object
streams.
Sound Audio HTTP
See “Working with video” on page 474.
Loads and plays supported audio formats.
XMLSocket XML TCP
See “Loading external sound files” on
page 443.
Exchanges XML messages with an XMLSocket
server.
Socket Any TCP
See “XML sockets” on page 801.
Connects to a TCP socket server.
SecureSocket (AIR) Any TCP with SSLv3
or TLSv1
See “Binary client sockets” on page 797.
Connects to a TCP socket server that requires
SSL or TLS security.
ServerSocket (AIR) Any TCP
See “Secure client sockets (AIR)” on page 797.
Acts as a server for incoming TCP socket
connections.
DatagramSocket (AIR) Any UDP
See “Server sockets” on page 805.
Sends and receives UDP packets.
See “UDP sockets (AIR)” on page 807
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